It’s conversational swearing — in the ‘hallways and in the classroom — that is on the rise, says Timothy Jay, one of the leading scholars on cursing in the United States.

Teens are more likely to drop casual expletives, or “fillers,” than the generation before them and have more trouble adjusting their conversation to fit their audience. That means adults — especially strangers who cannot sanction the teens — hear more of the same language that’ the teens’ friends hear, says Jay, author of “Why We Curse” and “Cursing in America.”